/*
 * Copyright 2019 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef SkStrikeSpec_DEFINED
#define SkStrikeSpec_DEFINED

#include "include/core/SkMaskFilter.h"
#include "include/core/SkPathEffect.h"
#include "include/core/SkRefCnt.h"
#include "include/core/SkScalar.h"
#include "include/core/SkSpan.h"
#include "include/core/SkString.h"
#include "include/core/SkTypeface.h"
#include "include/core/SkTypes.h"
#include "include/private/base/SkTemplates.h"
#include "src/core/SkDescriptor.h"
#include "src/core/SkScalerContext.h"

#include <memory>
#include <tuple>

class SkFont;
class SkGlyph;
class SkMatrix;
class SkPaint;
class SkStrike;
class SkStrikeCache;
class SkSurfaceProps;
struct SkPackedGlyphID;
namespace sktext {
class StrikeForGPU;
class StrikeForGPUCacheInterface;
}

class SkStrikeSpec {
public:
    SkStrikeSpec(const SkDescriptor &descriptor, sk_sp<SkTypeface> typeface);
    SkStrikeSpec(const SkStrikeSpec &);
    SkStrikeSpec &operator = (const SkStrikeSpec &) = delete;

    SkStrikeSpec(SkStrikeSpec &&);
    SkStrikeSpec &operator = (SkStrikeSpec &&) = delete;

    ~SkStrikeSpec();

    // Create a strike spec for mask style cache entries.
    static SkStrikeSpec MakeMask(const SkFont &font, const SkPaint &paint, const SkSurfaceProps &surfaceProps,
        SkScalerContextFlags scalerContextFlags, const SkMatrix &deviceMatrix);

    // A strike for finding the max size for transforming masks. This is used to calculate the
    // maximum dimension of a SubRun of text.
    static SkStrikeSpec MakeTransformMask(const SkFont &font, const SkPaint &paint, const SkSurfaceProps &surfaceProps,
        SkScalerContextFlags scalerContextFlags, const SkMatrix &deviceMatrix);

    // Create a strike spec for path style cache entries.
    static std::tuple<SkStrikeSpec, SkScalar> MakePath(const SkFont &font, const SkPaint &paint,
        const SkSurfaceProps &surfaceProps, SkScalerContextFlags scalerContextFlags);

    // Create a canonical strike spec for device-less measurements.
    static std::tuple<SkStrikeSpec, SkScalar> MakeCanonicalized(const SkFont &font, const SkPaint *paint = nullptr);

    // Create a strike spec without a device, and does not switch over to path for large sizes.
    static SkStrikeSpec MakeWithNoDevice(const SkFont &font, const SkPaint *paint = nullptr);

    // Make a strike spec for PDF Vector strikes
    static SkStrikeSpec MakePDFVector(const SkTypeface &typeface, int *size);

    sk_sp<sktext::StrikeForGPU> findOrCreateScopedStrike(sktext::StrikeForGPUCacheInterface *cache) const;

    sk_sp<SkStrike> findOrCreateStrike() const;

    sk_sp<SkStrike> findOrCreateStrike(SkStrikeCache *cache) const;

    std::unique_ptr<SkScalerContext> createScalerContext() const
    {
        SkScalerContextEffects effects{ fPathEffect.get(), fMaskFilter.get() };
        return fTypeface->createScalerContext(effects, fAutoDescriptor.getDesc());
    }

    const SkDescriptor &descriptor() const
    {
        return *fAutoDescriptor.getDesc();
    }
    const SkTypeface &typeface() const
    {
        return *fTypeface;
    }
    static bool ShouldDrawAsPath(const SkPaint &paint, const SkFont &font, const SkMatrix &matrix);
    SkString dump() const;

private:
    SkStrikeSpec(const SkFont &font, const SkPaint &paint, const SkSurfaceProps &surfaceProps,
        SkScalerContextFlags scalerContextFlags, const SkMatrix &deviceMatrix);

    SkAutoDescriptor fAutoDescriptor;
    sk_sp<SkMaskFilter> fMaskFilter{ nullptr };
    sk_sp<SkPathEffect> fPathEffect{ nullptr };
    sk_sp<SkTypeface> fTypeface;
};

class SkBulkGlyphMetrics {
public:
    explicit SkBulkGlyphMetrics(const SkStrikeSpec &spec);
    ~SkBulkGlyphMetrics();
    SkSpan<const SkGlyph *> glyphs(SkSpan<const SkGlyphID> glyphIDs);
    const SkGlyph *glyph(SkGlyphID glyphID);

private:
    inline static constexpr int kTypicalGlyphCount = 20;
    skia_private::AutoSTArray<kTypicalGlyphCount, const SkGlyph *> fGlyphs;
    sk_sp<SkStrike> fStrike;
};

class SkBulkGlyphMetricsAndPaths {
public:
    explicit SkBulkGlyphMetricsAndPaths(const SkStrikeSpec &spec);
    explicit SkBulkGlyphMetricsAndPaths(sk_sp<SkStrike> &&strike);
    ~SkBulkGlyphMetricsAndPaths();
    SkSpan<const SkGlyph *> glyphs(SkSpan<const SkGlyphID> glyphIDs);
    const SkGlyph *glyph(SkGlyphID glyphID);
    void findIntercepts(const SkScalar bounds[2], SkScalar scale, SkScalar xPos, const SkGlyph *glyph, SkScalar *array,
        int *count);

private:
    inline static constexpr int kTypicalGlyphCount = 20;
    skia_private::AutoSTArray<kTypicalGlyphCount, const SkGlyph *> fGlyphs;
    sk_sp<SkStrike> fStrike;
};

class SkBulkGlyphMetricsAndDrawables {
public:
    explicit SkBulkGlyphMetricsAndDrawables(const SkStrikeSpec &spec);
    explicit SkBulkGlyphMetricsAndDrawables(sk_sp<SkStrike> &&strike);
    ~SkBulkGlyphMetricsAndDrawables();
    SkSpan<const SkGlyph *> glyphs(SkSpan<const SkGlyphID> glyphIDs);
    const SkGlyph *glyph(SkGlyphID glyphID);

private:
    inline static constexpr int kTypicalGlyphCount = 20;
    skia_private::AutoSTArray<kTypicalGlyphCount, const SkGlyph *> fGlyphs;
    sk_sp<SkStrike> fStrike;
};

class SkBulkGlyphMetricsAndImages {
public:
    explicit SkBulkGlyphMetricsAndImages(const SkStrikeSpec &spec);
    explicit SkBulkGlyphMetricsAndImages(sk_sp<SkStrike> &&strike);
    ~SkBulkGlyphMetricsAndImages();
    SkSpan<const SkGlyph *> glyphs(SkSpan<const SkPackedGlyphID> packedIDs);
    const SkGlyph *glyph(SkPackedGlyphID packedID);
    const SkDescriptor &descriptor() const;

private:
    inline static constexpr int kTypicalGlyphCount = 64;
    skia_private::AutoSTArray<kTypicalGlyphCount, const SkGlyph *> fGlyphs;
    sk_sp<SkStrike> fStrike;
};

#endif // SkStrikeSpec_DEFINED
